A despondent Arsene Wenger had finished giving his press conference, when a voice cried out from the back of the room to ask if he would mind answering one question in French.

Wenger stood at the head of the media lounge. He didn’t respond, but nor did he depart, so the voice went on. What, it asked, was the most disappointing aspect of Arsenal’s performance?

You didn’t have to be fluent to understand Wenger’s answer: “notre naïveté”.

Naive is a word that has become synonymous with Arsenal. As a bit of a test, I ran it through the search engine on my own blog. Here are the most recent uses:

“We all know that Arsene Wenger isn’t going anywhere until 2017. With that in mind, we have no choice but to demand more from the players. They can’t hide behind his diminishing reputation. They might not like it, but this is their mess too.It’s never just one thing, and Wenger’s tactical naivety does not fully excuse theirs.”

Then:

“However, neither of those can match the humiliation of losing 6-0 at Chelsea. The tactical naivety Arsenal showed in that game is what makes me a little concerned about the length of Arsene Wenger’s new deal.”

Then:

“Wenger was comprehensively outmanoeuvered by Roberto Martinez at Goodison Park. In a game in which a point would have been a good result for Arsenal, it’s tempting to call Wenger’s tactics naive. However, considering how long he’s been in the game, one has to revert to an altogether more damning adjective: negligent.”

I gave up at that point. Not even I am so morbid as to dig deeper in to the mire.

However, you might see what I’m getting at. Naivety ought to be a temporary thing. It’s a state of being characterised by a lack of experience or sophistication. That should get better. It should be fixable. And yet here we are, approaching the end of a decade of defensive guilelessness. We’re a team caught in arrested development.

Google “how to stop being naive” and it’ll tell you the process can be accelerated by having your heart broken. Well, that one doesn’t seem to have worked for us. The painful lessons keep on coming, and we keep on ignoring them.

What happened against Monaco approached the absurd. Going 2-0 down was bad enough, but to concede a third having dragged ourselves back in to the game was madness. The craziest part is that I wasn’t even surprised. How many times have we seen Arsenal carelessly chase goals, only to be sucker-punched?

This latest horror show arrives days after we came inches from surrendering a 2-0 lead in the final few minutes at Crystal Palace. The further away it gets, the more that Manchester City win feels like an anomalous result against an out-of-sorts side.

Arsenal will re-qualify for the Champions League, but last night was a reminder of why it’s unlikely to get significantly better than that any time soon. You can look at our annual top four finish as a remarkable piece of consistency. Alternatively, you can see it as a staggering lack of progression — evidence that the teams of the second half of Arsene’s reign have been chronically hampered by an unworldliness the manager seems powerless to fix. We’re good, but unless something changes we’ll never be good enough.

It’s all very well for Arsene to accuse his players of naivety, but he is the man charged with educating this squad. If naivety is the problem, better coaching is surely the cure.